Using a serrated knife, level tops of cakes if vital. Cut every cake horizontally in 1/2. Spread 1 half of of every cake with jam. Thinly spread 1/3 cup buttercream icing over jam. Sandwich with cake tops. Place cakes on forums. Thinly spread tops and aspects of desserts with ultimate buttercream icing.

Knead final white icing until clean. Using a rolling pin, roll icing out until 1mm thick and large enough to cover 23cm cake (around 38cm rectangular). Gently raise icing over cake. Dust arms with icing sugar. Using arms, smooth icing. Ease icing around facets and base of cake, pushing icing in and round base. Using a sharp knife, trim excess icing.

Make royal icing: Lightly whisk eggwhite and lemon juice collectively in a bowl. Gradually upload icing sugar, whisking until smooth and blended.

Cut ribbons to suit across pinnacle and down facets of every cake (round 28cm-lengthy and 36cm-long). Using photograph as a manual, function ribbons on cakes. Secure at ends with royal icing. Using a palette knife, push ends below cake. Place 15cm cake and board on top of huge cake on an perspective.

Spoon ultimate royal icing right into a piping bag geared up with a 5mm fluted nozzle. Pipe icing around backside area of each cake. Stand for 1 hour to set. Serve.